1. Technical Field
The invention relates to a light source, and more particularly to a white color light source of an organic light emitting diode which is used for irradiating on plants.
2. Description of Related Art
In the plant growth process, irradiation is essential. Currently, manufacturers use artificial illumination system to provide sufficient and proper lights for plants, so as to accelerate the growth thereof or improve the quality thereof. For example, incandescent lamps, fluorescent lamps, light emitting diodes, or laser diodes have been used as illumination source for plant lighting. However, each of them is not faultless, and therefore application thereof is limited.
In detail, light emitting efficiency of the incandescent lamps and the fluorescent lamps is not high, and they may generate too much heat, which causes plants prone to be burned. In addition, since the incandescent lamps or the fluorescent lamps are point or line light sources, which are not planar light sources, the distance between the lamps and plants is increased for uniform irradiation. Therefore, disposition of the incandescent lamps or the fluorescent lamps occupies more space. Furthermore, each of these light sources has a certain frequency spectrum, and thus it is hard to adjust an intensity of a frequency spectrum of a specific wavelength according to properties of plants for accelerating the growth thereof. On the other hand, a planar-like light source may be formed by arranging the light emitting diodes or laser diodes in array, so that the distance between the light sources and plants can be reduced. However, driver module arranging in high density have drawbacks of complicated assembly and high heat generation, which cause reliability of the source system decreased.